Before any sort of surgery, its routine to clean the skin with antiseptic. The point is to kill the microorganisms on the skin and so hopefully reduce the chance of infection. The two most common preoperative skin antiseptics are povidone-iodine and chlorhexidine. Both of these come in an alcoholic or aqueous preparation. So which is better for preventing wound infections? Iodine or chlorhexidine? And does it matter if it’s in alcohol or in water?

Bottom Line:

According to the best available evidence, cleaning the skin with chlorhexidine seems to be superior to iodine in terms of reducing surgical site infections. The evidence for chlorhexidine with alcohol versus iodine in water is strong, while the evidence for chlorhexidine in alcohol versus iodine in alcohol is of poorer quality but nonetheless in favour of chlorhexidine. Furthermore, for simple skin excisions done in the general practice setting, it doesn’t matter if you use chlorhexidine in alcohol or chlorhexidine in aqueous solution. Despite all of this, rates of surgical site infections with simple skin excisions are pretty uncommon regardless of what you use and so if you love operating on jaundiced looking skin, you could make a case for iodine.